Purpose

Using turbulators, obstacles, ribs, corrugations, baffles and different tube geometry, and also various arrangements of these components have a noticeable effect on the shell and tube heat exchangers (STHEs) thermal-hydraulic performance. This study aims to investigate non-Newtonian fluid flow characteristics and heat transfer features of water and carboxyl methyl cellulose (H₂O 99.5%:0.5% CMC)-based Al₂O₃ nanofluid inside the STHE equipped with corrugated tubes and baffles using two-phase mixture model.

Design/methodology/approach

Five different corrugated tubes and two baffle shapes are studied numerically using finite volume method based on SIMPLEC algorithm using ANSYS-Fluent software.

Findings

Based on the obtained results, it is shown that for low-mass flow rates, the disk baffle (DB) has more heat transfer coefficient than that of segmental baffle (SB) configuration, while for mass flow rate more than 1 kg/s, using the SB leads to more heat transfer coefficient than that of DB configuration. Using the DB leads to higher thermal-hydraulic performance evaluation criteria (THPEC) than that of SB configuration in heat exchanger. The THPEC values are between 1.32 and 1.45.

Originality/value

Using inner, outer or inner/outer corrugations (outer circular rib and inner circular rib [OCR+ICR]) tubes for all mass flow rates can increase the THPEC significantly. Based on the present study, STHE with DB and OCR+ICR tubes configuration filled with water/CMC/Al₂O₃ with f = 1.5% and d_np = 100 nm is the optimum configuration. The value of THPEC in referred case was 1.73, while for outer corrugations and inner smooth, this value is between 1.34 and 1.57, and for outer smooth and inner corrugations, this value is between 1.33 and 1.52.

中文翻译：

---

装有折流板和装有非牛顿两相纳米流体的波纹管的管壳式换热器热工水力分析

目的

使用湍流器，障碍物，肋，波纹，挡板和不同的管道几何形状，以及这些组件的各种布置方式，对壳管式热交换器（STHEs）的热工液压性能也具有显着影响。本研究旨在研究装有波纹管和折流板的STHE内部基于水和羧基甲基纤维素（H ₂ O 99.5％：0.5％CMC）的Al ₂ O ₃纳米流体的非牛顿流体流动特性和传热特性。相混合模型。

设计/方法/方法

利用ANSYS-Fluent软件，基于SIMPLEC算法，采用有限体积法对五个不同的波纹管和两个折流板的形状进行了数值研究。

发现

根据获得的结果，表明，对于低质量流量，盘式挡板（DB）的传热系数比分段挡板（SB）的传热系数大，而对于质量流量大于1 kg / s的情况，使用SB会比DB配置带来更多的传热系数。与热交换器中的SB配置相比，使用DB可获得更高的热液压性能评估标准（THPEC）。THPEC值在1.32和1.45之间。

创意/价值

使用内，外或内/外波纹（外圆肋和内圆肋[OCR + ICR]）管的所有质量流量均可显着提高THPEC。根据目前的研究，具有DB和OCR + ICR管的STHE填充水/ CMC / Al ₂ O ₃且f = 1.5％和d _np = 100 nm的配置是最佳配置。在所述情况下，THPEC的值为1.73，而对于外部波纹和内部光滑，该值在1.34至1.57之间，对于外部光滑和内部波纹，该值在1.33至1.52之间。